Artist pastels and chalks in the conventional round or square stick-like format are well known. Different kinds of storage containers and packaging have been developed to store and transport stick-format pastels and chalks. Case and tray arrangements and other types of storage containers for stick-format pastels and chalks are shown, for example, in U.S. Pat. Nos. 4,616,748, 5,388,689, 5,860,518 and 6,698,585.
Pan-like containers, such as godets or compacts, have long been used to hold pressed powder formulations for cosmetic applications. These cosmetic containers come in a variety of shapes (e.g., round, square, half-round, etc.) and configurations (e.g., lid, no lid, multiple compartments, etc.). The containers are typically made of plastic or metal with a flat bottom and sides at a right angle to the bottom portion. In some of these containers, the bottom portion can include ridges that increase the structural integrity of the container. Recent examples of improvements in the design of such cosmetic containers are shown, for example, in U.S. Publ. Appl. No. 2005/0109363 and Japanese Abstracts Nos. JP/9098830 and JP/2057203.
Because of safety concerns, the compositions of cosmetics are closely regulated by the Food and Drug Administration (FDA). While certain types of cosmetics, such as lipstick, can be provided in either a stick format or a pan format, pressed powder cosmetics like eye shadow and blush are only available in a pan format where an applicator of some type (e.g., a brush or sponge) is used to apply the cosmetic. There is no direct application of a pressed powder material in stick format for cosmetics. One reason is that the pressed powders for cosmetics are generally softer than, for example, sticks of chalk or pastels. Another reason is that the amount of pigment in pressed powder cosmetics is typically quite low (i.e., <10% and typically only about 2-3%), while the amount of fillers and binders is much higher (i.e., >50%). Because the pressed powder cosmetic is applied directly to the skin, the amount of pigment that can be used is necessarily limited to avoid problems of biocompatibility, removability and long term effect of the cosmetic material.
U.S. Pat. No. 6,524,597 describes the conventional problems and techniques for manufacturing pressed powder cosmetic materials. This patent teaches a new composition for pressed powder cosmetics using a surface treatment with a fluorine compound. The resulting cosmetic pressed powder has a smooth feel and overcomes the problems of cracking and caking that occur when the hardness or durometer of the pressed powder composition is decreased.
Pressed powder cosmetic formulations can be fragile, and can easily break, chip or crack during application and/or storage of the pressed powders. Generally, pressed powder cosmetic formulations with a higher percentage of binders and/or formulations pressed at a higher pressure tend to be less fragile than those pressed at a lower pressure or with less binder content. However, as the pressed powder cosmetic is removed from the container and the level of pressed powder approaches the bottom surface of the container, the remaining pressed powder cosmetic in the container tends to become ever more fragile and prone to breakage. This is an undesirable characteristic as the remaining material that is cracked or broken is generally unusable, and is thus wasted.
Japanese Abstract No. JP/9098830 describes one embodiment of a container for pressed powder cosmetics in which a hot melt adhesive is used as part of the manufacturing process to aid in retaining the cosmetic pressed powder in the container. The use of such a holt melt adhesive, however, could have significant impact on the biocompatibility and toxicity of the cosmetic material due to both the heating of the pressed powder that can affect coloration of the pigment components and the potential leaching of the hot melt adhesive into the pressed powder composition.
While there have been numerous containers and compositions developed for pressed powder cosmetics, these techniques and approaches are geared toward the regulatory and other requirements specific to cosmetic materials. As a result, there have been few attempts to bring any of the teachings related to pressed powder materials from the field of cosmetics into the field of artist materials and equipment.